Improvement in valves for steam-engines



y UNITED STATES PATENT" OFFICE.`

D. R. FRASER, OF CHICAGO, IIJLINOIS, ASSIGNOR TO HIMSELF, P. W. GATS, AND THOMAS CHALMERS, OF SAME PLACE.

IMPROVEMENT IN VALVES FOR STEAM-ENGINES.

, l Specification forming part of Letters Patent No. 34,997, dated April 15, -1862.

To all whom it may concern:

Be it known thatI, I). R. FRASER, of Chicago, in the county of Cook and State of Illinois, have invented anew and useful Improvement in Anti-Friction Slide-Valves; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming partof this specification, in which- Figure 1 is a vertical longitudinal sect-ion of a slide-valve with my improvements applied to it. Fig. 2 is a vert-ical transverse section of the same. Fig. 3 is a horizont-al section in the line of Figs. l and 2. Figs. 4. 5, and 6 are modifications of valve attachments suspended according to one part` of my invention.

Similar` letters of reference in the several figures indicate corresponding parts.

The nature of my invention consists in a pendulous balance block or plate, in combination with a gravitating ring vor rectangular frame and the platform of a slide-valve, whereby an improved arrangement of antifriction slide-valve is obtained; second, in the use of a vertical hanger with spherical seat on its lower end for suspendingthebalancing mechanism of the valve; third,in the combination of vertical pins with spherical termini and the balancing mechanism of the valve; fourth, in the combination of springs and the balancing mechanism of the valve; fifth, in the combination of a slotted wedge, inclined projection of the valve-connecting rod, and retaining-nuts.

To enable others skilled in the art to make and use my invention, I will proceed to v de scribe the saine with reference to the drawings.

A is the face or valve-seat of the enginecylinder; B, an ordinary slide-valve with a platform C added on the back of the same; fD D, a rectangular frame resting on the platform. This frame is ground on its bottom and on its inner sides; so, also, is the platform C on its upper surface. The fra-me D D is open at top and bottom, so as to present but a narrow wearing-surface to the platform and to admit a balance-block Within it.

E is a rectangular balance-block with a vertical iiange on its under side, said tiange be ing ground on its outer surface, so as' to tit steam-tight against the sides of the. frame D D. This block extends down into the frame a suitable distance to maintain a connection therewith, and ,is suspended in this position by means of a vertical bolt F, with a ball joint or seat F on its lower end, said bolt extending down from the top of the steam-chest Gand the ball fitting loosely, but steam-tight in a spherical socket H, formedwin the under side of the balance-block, as shown. Y.

Between stops a a of the balance block and the rectangular frame D D, at each` end, a spring H is arranged so as to control any up movement of the frame and hold said frame with a yielding force down upon the` the rear end of the va1veand the connectingarm M of the valve `passes through it. far enough to receive on its end retaining-nuts c c, similar nuts d being provided on the arm at the front end of the valve. Byslackening the nuts and lowering the wedge it is obvious that the slack will be taken up.

In Fig. et the balance-block E is inform of a flanged circular disk, and is supported by the bolt with spherical end within a chamber of the steam-chest cover, as shown, and the frame D D, instead of being rectangular at the points where the connection between it and the balance-block is effected, is made with a raised circular hanged', said flange extending up within the circular flange e of the disk E, as shown; orthe fia-nge e may extend down within the flange fl. In either case the` iianges must be ground so as to form f spring being interposed between a solid shoulder of the rectangular frame D D, which in this case is closed in at top, as shown.

surrounded, steam-tight, by the frame-D D, i

and the valve-back closed in by said frame and block from the pressure of the steam, the

valve works nearly on a balance, the pressure ofthe steam above the inclosed part of the platform of the valve being borne by the balance-block instead ot' bythe valve. The block isfree to move to accommodate the valve in all directions upon the spherical seat of the bolt, but is kept in proper position by means of the springs and pins with spherical heads, and while so moving the rectangularpackingframe automatically adjusts itself upon the valve and around the balance-block in such manner that the joints are kept steam-tight,

or as nearly so as practicable. The springs of course press down upon this frame D; but the frame does not depend upon them for its position, as its own gravity insures a proper adjustment. This I believe is a new feature is concerned. The principle of balancing is different, the steam in these instances acting against the balance-block with an upward pressure and upon the top of the frame with a downward pressure, and as the balance'- block E is of less area than the frame D the superior pressure is upon the frame; but at the same time the relief offered to the Valve by the balance-block causes it to work almost on a balance. These plans are not so good as the others.

What I claim as my invention, and desire to secure by Letters Patent, is-

i. The combination and arrangement of the suspended and 'universally-moving balanceblock E, gravitating frame or packing D D, and platform C of lslide-valve, substantially in the manner and foi" the purposes described.

2. The vertical bolt F, with spherical seat on its lower end for`suspending the balancing mechanism of the valve, substantially in the manner and for the purpose described.

3. The combination of the vertical pins I, with spherical ends, and the bolt F F and balancing mechanism, substantially in the manner described.

4. The combination of the springs, bolt F F', pins I, and balancing mechanism, substantially in the manner and for the purpose dc' scribed. l 5.- The combination of the slotted wedge J, inclined projection K, connecting-arm M, retaining-nuts c c, and valve B, substantially in the manner and for the purpose described.

D. R. FRASER.

Witnesses: l i

HIRAM-H. SCovILLE, LovELL D. TURNER. 

